Answer:
Both tests test the endurance and strength of muscle, but they evaluate muscles in different areas of the body. The curl-up test is used for the abdominal muscles while the arm hangs test, as is said in its name, test the arm muscles.
Explanation:
In a curl-up test, the person has to do as many curl-ups as she or he can following a cadence. This exercise tests the endurance and strength of abdominal muscles, which are necessary to have a good posture.
In an arm hang test, what is measured is the endurance and strength of a different group of muscles. During this test, the person has to grab a horizontal bar and hang himself herself from it, and the chin must be above it. The aim is to hold this position for as long as possible.
We can see that both tests measure the same things but for specifics parts of the body and using different techniques, this is why they can not be interchangeable.
